Diversity and Dynamics of Microbial Ecosystem on Berry Surface During the Ripening of Ecolly Grape in Wuhai, China

Abstract The structural and functional diversity of the microbial ecosystem on the grape surface affect the health of berries and the flavor of wines, which are also changed by many factors such as climate, weather conditions, agronomic practices, and physiological development. To understand and explore the natural characteristics of grape surface microbial ecosystem during ripening, the species composition and dynamics of fungi and bacteria communities on the skin of Ecolly grape were determined by Illumina Novaseq platform sequencing. The results showed that 2146 fungal OTUs and 4175 bacterial OTUs were obtained, belonging to 4 fungal phyla and 20 bacterial phyla, and Shannon index indicated that the fungus community had the highest species diversity at the véraison stage and the bacteria community at the harvest stage. The four dominant fungal genera during grape ripening included Alternaria, Naganishia, Filobasidium, and Aureobasidium, which accounted for 82.8% of the total fungal community, and the dominant bacterial genera included Sphingomonas, Brevundimonas, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, and Massilia, which accounted for 77.9% of the total bacterial community. The species richness and diversity in the grape microbial ecosystem are constantly changing during the maturation stages, and there are complex interactions and correlations between related core microbial genera, which may have an important impact on the function and ecological role of the community. This study provides a basis for understanding the natural characteristics of the microbial ecosystem on the grape surface during the grape ripening, and the sustainable production concept of the microecology driving the viticulture management system.